MRI compatible patient trolley

ABSTRACT

A trolley system configured to transport a patient within an MRI environment includes a patient support portion, a base portion configured for movement relative to a floor, a lift coupled to the patient support portion and the base portion, an electric motor coupled to the lift, and an electric blower coupled to the patient transfer device. The lift is configured to change the elevation of the patient support portion relative to the base portion. The motor is mounted such that the elevation of the motor is fixed relative to base portion. The trolley system is positionable adjacent an MRI apparatus within the MRI environment and the magnetic field of the MRI does not interfere with the operation of the motor or blower. The trolley system may further include a patient transfer device having an air bearing. The blower is configured to deliver air to the air bearing.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Phase Application of PCTInternational Application PCT/US2016/057108, filed on Oct. 14, 2016,which claims the benefit of U.S. provisional patent application entitled“MRI COMPATIBLE PATIENT TROLLEY,” which was filed on Oct. 14, 2015 andassigned Ser. No. 62/241,403, and U.S. provisional patent applicationentitled “PATIENT TROLLEY AND PATIENT TRANSFER DEVICE,” which was filedon Oct. 14, 2015 and assigned Ser. No. 62/241,400. The entire contentsof the foregoing provisional applications are incorporated herein byreference in their entirety.

FIELD OF THE INVENTION

The present invention generally relates to patient trolleys, associatedsystems, and methods for transporting patients and providing safetransfer of a patient from the patient trolley to a target modalityduring medical procedures or diagnostic determinations.

BACKGROUND OF THE INVENTION

Patient trolleys are used frequently in hospitals and treatment centersto safely transport patients to various locations within the facility.When the patient requires therapy or diagnostic imaging, the patienttrolleys are used to deliver the patient in proximity to certain targetmodalities. Target modalities may include various patient supportsurfaces associated with machines, such as CT, MR, and PET, an operatingtable, a hospital bed, an OR table, a treatment machine, roboticsurgical arms, etc. Patient trolleys are expected to safely transport apatient to and from various target modalities. Often these patients mustbe immobilized to maintain positional accuracy and consistency from onemodality to the next.

In order to transfer a patient from the top surface of a patient trolleyto the surface of a target modality, patient transfer devices arecommonly used. For patients that are not ambulatory and are expected toremain lying down, including in supine, prone, or recumbent positions,patient trolley operators should transport the patient trolley to alocation that is as close as possible to the surface of the targetmodality. Additional adjustments can be made by lifting or raising theelevation of the top surface of the patient trolley and transferring thepatient using the patient transfer device by sliding the patienttransfer device from the top surface of the patient trolley to the topsurface of the target modality. MRI environments in particular presentobstacles to the use of a patient trolley and transfer device. Due tothe tremendous strength of the magnetic field generated by an MRImachine, ferromagnetic materials can present a hazard in an MRIenvironment and therefore are carefully monitored and typically limited,complicating the construction of any device for use in and around theMRI machine.

Thus, a need exists for improved patient trolleys that not only providesafe transport of patients, but also facilitate easier patient transferto target modalities within an MRI environment. These and other needsare addressed by the patient trolley and associated systems and methodsof the present invention.

SUMMARY OF THE INVENTION

In one aspect of the present invention, a trolley system configured totransport a patient within an MRI environment comprises a patientsupport portion configured to support the patient, a base portionconfigured for movement relative to a floor, at least one actuatorcoupled to the patient support portion and the base portion, the atleast one actuator being configured to move the patient support portionrelative to the base portion, including but not limited to, changing theelevation of the patient support portion relative to the base portion,and at least one electric motor coupled to the at least one actuator,said actuator causing motion in at least one degree of freedom selectedfrom, but not limited to, a rotary stage, a linear stage, a telescopingstage, a pneumatic stage, a hydraulic stage, a scissor lift, etc. The atleast one electric motor may be mounted such that the elevation of theat least one electric motor is fixed relative to the base portion.Furthermore, when the trolley system is positioned adjacent an MRIapparatus within the MRI environment, the magnetic field of the MRI doesnot interfere with the operation of the at least one electric motor. Thetrolley may also comprise a plurality of actuators and electric motors.

In another aspect of the present invention, a trolley system configuredto transport a patient within an MRI environment comprises a patientsupport portion configured to support the patient, a base portionconfigured for movement relative to a floor, and an electric blowercoupled to the base portion and fixed to prevent movement of the blowerrelative to the trolley system, the blower being configured to deliverair to a feature, such as a feature located on the patient transferdevice, a feature located on the trolley, an accessory feature, or afeature located on the target modality. When the trolley system ispositioned adjacent an MRI apparatus within the MRI environment, themagnetic field of the MRI does not interfere with the operation of theblower.

The trolley system may further comprise a base portion, at least oneactuator coupled to the patient support portion and the base portion,and at least one electric motor coupled to the actuator. The at leastone actuator may have at least one telescoping stage and be configuredto move the patient support portion relative to the base portion andchange the elevation of the patient support portion relative to the baseportion. The at least one electric motor may be mounted such that theelevation of the at least one electric motor is fixed relative to thebase portion, and such that the magnetic field of the MRI does notinterfere with operation of the at least one electric motor. The trolleysystem may also comprise a battery for powering the at least oneelectric motor and the electric blower. A detachable hose may be used tocouple the patient transfer device to the blower.

In yet another aspect of the present invention, a method of delivering apatient to a bore of an MRI device by using a trolley system. Thetrolley system may include a patient support portion configured tosupport the patient, a patient transfer device comprising an air bearingon the patient support portion, a base portion configured for movementrelative to a floor, an actuator coupled to the patient support portionand the base portion, and one or more electric motors coupled to theactuator, all of the one or more electric motors being mounted such thatthe elevation of the electric motors is fixed relative to base portion.The method may comprise positioning a trolley system proximate to thebore of the MRI device, such that either end of the trolley system isfacing the bore of the MRI device, optionally raising the patientsupport portion relative to the base portion by actuating the actuatorto change the elevation of the patient support portion, providing air tothe air bearing, and transferring the patient transfer device from thepatient support portion to the target modality, wherein a pull force onthe trolley system by a magnetic field of the MRI device is less than orequal to 50 lbs force (and more preferably less than or equal to 25 lbsforce) as measured in connection with a nominal 3T MRI device.

In yet another aspect of the present invention, a method of transferringa patient to a target modality within an MRI environment comprises:

-   -   positioning a trolley system adjacent the target modality within        the MRI environment, the trolley system including        -   a patient support portion configured to support the patient,        -   a patient transfer device comprising an air bearing on the            patient support portion,        -   a base portion configured for movement relative to a floor,        -   an actuator coupled to the patient support portion and the            base portion, and        -   one or more motors coupled to the actuator, all of the one            or more motors being mounted such that the elevation of the            motors is fixed relative to base portion,    -   optionally raising the patient support portion relative to the        base portion by actuating the actuator to change the elevation        of the patient support portion;    -   providing air to the air bearing; and    -   transferring the patient transfer device from the patient        support portion to the target modality,

wherein the magnetic field of the MRI does not interfere with theoperation of all of the one or more motors during actuation of theactuator.

According to yet another aspect of the present invention, a method ofdelivering a patient to a bore of an MRI device comprises positioning atrolley system proximate to the bore of the MRI device, such that an endof the trolley system is facing the bore of the MRI device, actuatingthe electric blower to deliver air to the patient transfer device,thereby supplying air to the patient transfer device to facilitatemovement of the patient, and conveying the patient onto a targetmodality. The trolley system may be MR Compatible with a maximummagnetic attraction force less than or equal to 50 lbs force and includea patient support portion configured to support the patient, a patienttransfer device positioned on the patient support portion, a baseportion configured for movement relative to a floor, and an electricblower.

In yet another aspect of the present invention, an imaging system isprovided comprising an MRI device, a target modality, a trolley system,and a patient transfer device configured for movement relative to apatient support portion of the trolley system.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top perspective view of a patient trolley and transferdevice according to an embodiment of the present invention next to atarget modality in an MRI environment;

FIG. 2 is a side view of the patient trolley and transfer device of FIG.1 within a magnetic field of an MRI machine;

FIG. 3 is a side view of the patient trolley and transfer device of FIG.1;

FIG. 4 is a schematic side view of the chassis of a patient trolleyaccording to another embodiment of the present invention;

FIG. 5 is a top perspective view of an embodiment of a lift or actuatorfor a patient trolley according to another embodiment of the presentinvention; and

FIG. 6 is a schematic top plan view of the relative position of atrolley and an MRI device when determining the pull force on the trolleysystem.

DETAILED DESCRIPTION OF THE INVENTION

The invention is described by reference to exemplary embodiments andvariations of those embodiments. Although the invention is illustratedand described herein with reference to specific embodiments, theinvention is not intended to be limited to the details shown anddescribed. Rather, various modifications may be made in the detailswithin the scope and range of equivalents of the claims and withoutdeparting from the invention.

According to one aspect of this invention, an imaging system is providedcomprising an MRI, a target modality, a trolley system, and a patienttransfer device configured for movement relative to a patient supportportion of the trolley system. The patient transfer device optionallyincludes an air bearing attached to the underside of the patienttransfer device. The imaging system may be combined with a source of lowpressure/high volume air coupled to the patient transfer device andconfigured to deliver air to the air bearing. For example a lowpressure/high volume air source may be 0.1 to 5 PSI and 50 to 200 CFM.The air bearing can be of many designs as known to those skilled in theart, including but not limited to, a bladder, a cushion, etc. Thetrolley system may include at least one actuator, providing at least onedegree of motion. The air source provides air flow to the air bearingand facilitates the transfer of the patient from the top surface of thetrolley to the patient surface of the target modality.

Also, the trolley system may include an actuator configured to adjustthe elevation of a patient support surface relative to a base portion.An actuator may include a lift, a linear stage, a rotary stage, ascissoring mechanism, or any mechanism capable of changing the relativeposition between two components. The actuator includes, or is coupledto, a motor. When actuated, the motor raises or lowers the elevation ofthe patient support surface.

Motors for the trolley actuator and blowers used for the operation ofthe trolley and patient transfer devices may be made of ferromagneticmaterials and/or include electrically powered components. The magneticfield can disrupt the operation of the motors, and the ferromagneticmaterials can be attracted to the magnetic field of the MRI, thusthreatening the safe operation of the trolley and transfer devices. Thisinvention mitigates this risk through placement of the motor and othercomponents to ensure their proper functioning and to reduce magneticattraction in the MRI environment. As a result, the systems according tothe embodiments described herein may be compatible with the MRIenvironment. As used herein throughout the specification and the claims,the term “MR Compatible” refers to the magnetic attraction force of thetrolley system and the operability of one or more electric motors of thetrolley system as determined by the MR Compatibility Test Proceduredescribed in the Examples section below.

Regarding the magnetic attraction force of the trolley system, it hasbeen surprisingly discovered that a multi-functional trolley system canbe provided according to aspects of this invention while still having amagnetic attraction force that renders the trolley system suitable foruse in an MRI environment such as an MRI room. According to embodimentsof the invention, the maximum magnetic attraction force is less than orequal to 50 lbs force, and more preferably less than or equal to 25 lbsforce, as determined by the MR Compatibility Test Procedure described inthe Examples section below.

Regarding the operability of one or more electric motors of the trolleysystem, it has been surprisingly discovered that a trolley system havingone or more electric motors can be provided according to aspects of thisinvention while still remaining operable in an MRI environment such asan MRI room. According to embodiments of the invention, operability ofone or more electric motors of the trolley system is maintained, asdetermined by the MR Compatibility Test Procedure described in theExamples section below.

Previously, portable blowers have been provided with long hoses for thepatient transfer device, so that the blower motor can remain outside ofthe MRI environment (in practice, outside the MRI room) while thepatient is transferred to avoid an unsafe situation. However, it ispreferred to avoid the need for such a blower arrangement with longhoses and electrical cords.

By affixing the blower to the trolley according to aspects of thisinvention, the location and orientation of the blower relative to theMRI machine is controlled such that its function is not impeded. Inaddition, it has been discovered that the trolley, which is composedprimarily of non-ferromagnetic materials, is of sufficient mass thatprovides an anchoring function for the blower and other featurescontaining ferromagnetic components. This prevents the blower from beingdangerously pulled toward and into the MRI machine. Providing a batterypower source eliminates the need for electrical cords thereby enablingthe unit to be self-contained. Tripping hazards and MRI interferencefrom the electrical cord can also be avoided.

Additionally, it is desirable to optionally use a vacuum pump motor inan MRI environment. Such vacuum pump motors are useful for, among otherthings, forming vacuum cushions for use during MR imaging. According toaspects of this invention, one or more vacuum pump motors is mounted tothe trolley system.

Referring generally to the Figures, the present invention provides atrolley system 14 configured to transport a patient within an MRIenvironment such as an MRI room, the trolley system 14 comprises apatient support portion configured to support the patient, stowable siderails 21 on either side of the patient support portion, a base portion15 configured for horizontal movement relative to a floor, at least onelift or pillar 22 a, 22 b coupled to the patient support portion and thebase portion 15, the at least one lift or pillar 22 a, 22 b beingconfigured to move the patient support portion relative to the baseportion 15 and to change the elevation of the patient support portionrelative to the base portion 15, and at least one motor 24 a, 24 bcoupled to the at least one lift 22 a, 22 b. The at least one motor 24a, 24 b is mounted such that the elevation of the at least one motor 24a, 24 b is fixed, or limited, relative to the base portion 15, and thetrolley system 14 is positionable adjacent an MRI apparatus 10 withinthe MRI environment and the magnetic field of the MRI 10 does notinterfere with the operation of the at least one lift 22 a, 22 b, or atleast one blower 19. Alternatively, the motor of the at least one lift22 a, 22 b may be mounted to the lower portion of the lift in such a waythat the displacement of the motor with respect to the base portion islimited or prevented, such that the motor remains within a weakerportion of the magnetic field.

In another embodiment of the present invention, a trolley system 14configured to transport a patient within an MRI environment comprises apatient support portion configured to support the patient, a patienttransfer device 16 configured for movement relative to the patientsupport portion, the patient transfer device 16 providing an airbearing, and a blower 19 coupled to the patient transfer device 16 andfixed to prevent movement of the blower 19 relative to the trolleysystem 14, the blower 19 being configured to deliver air to at least onefeature of the trolley system 14 (such as the air bearing). The featuremay be selected from the group consisting of a patient transfer deviceor other accessory features, such as a patient bed, a wound care bed, abed that provides alternating pressures, a surface designed fortherapeutic applications, a surface designed for patient comfort, a skinprotection surface, an air powered device, and a compression surface.The feature may also include other accessories known to one skilled inthe art. The trolley system 14 is positionably adjacent an MRI apparatus10 within the MRI environment and the magnetic field of the MRI 10 doesnot interfere with the operation of the blower 19.

Referring to each of the figures more specifically, wherein likereference numerals used in the figures denote like parts throughout thevarious figures, a patient trolley 14 according to an embodiment thepresent invention is illustrated in FIG. 1 within an MRI environment.The patient trolley 14 is adjacent to an MRI table 12 and is locatednear the bore of an MRI machine 10. The patient trolley 14 includes apatient transfer device 16 to facilitate transfer from the top of thepatient trolley 14 to the patient support surface 17 of the MRI table12. The base portion 15 of the patient trolley 14 includes a connectinghub 20 to provide a connection via a hose 18 to the patient transferdevice 16. The connecting hub 20 also provides a portal facilitatingconnections between the system electronics and the top of the patienttrolley 14.

Transfer of a patient from the patient trolley 14 to the MRI table 12 isfacilitated by delivering air to an air bearing (not shown) on theunderside of the patient transfer device 16 by using the blower 19. Thisair bearing reduces the friction between the patient transfer device andthe surface along which it travels.

The magnetic field strength of most commercial MRI machines used fordiagnostic imaging for humans is within the range of 0.35 to 3 Tesla.However, this rating only describes the maximum strength of the magneticfield within the bore of the MRI machine. As illustrated in theschematic illustration of FIG. 2, the magnetic field strength of the MRImachine 10 decreases with distance. The force exerted on anyferromagnetic components is related to the field strength where thecomponents are located. Because portions of the patient trolley will beclose to the bore of the MRI machine when the patient trolley is inposition to transfer the patient, it is preferred that non-ferromagneticmaterials are used to manufacture the patient trolley, particularly thetop and leading portions of the patient trolley, which will be in closeproximity to the MRI machine.

Due to physical property requirements or cost demands, it may beimpractical to include components made solely from non-ferromagneticmaterials. In order to further minimize the potential effects of themagnetic field from the MRI machine on the patient trolley, thecomponents, specifically the components having moving parts, areconfigured, such that the components remain fixed or at least arepositioned near the base of the patient trolley. Assuming that the MRImachine has the magnetic field profile of a typical 3T machine (such asthe magnetic field profile illustrated in FIG. 2), the base portion 15of the patient trolley 14 will be exposed to magnetic field strengthsgenerally no greater than 200 mT due to the location of the base portion15 relative to the MRI machine 10.

Referring now to the embodiment illustrated in FIGS. 3 to 5, the patienttrolley 14 includes a top portion having a top surface on which apatient transfer device 16 is located. Stowable side rails 21 are alsolocated along the sides of the top portion. The patient transfer device16 includes a hose connector 17 to receive one end of a hose 18. Thehose 18 preferably has two sections. The top section has two opposingends in which one end is connected to the hose connecter 17 of thepatient transfer device 16 and the opposite end is connected to a topportion of the trolley 14. The bottom section of the hose 18 also hastwo opposing ends with one end being connected to the top portion of thetrolley 14 and the opposite end connected to a blower 19 located in thebase portion 15 of the patient trolley 14, and should be of sufficientlength to provide enough slack to accommodate the full height range ofthe trolley top 14. While various blowers can be utilized, one exemplaryblower is available from AMETEK Corp. (e.g., AMETEK Lamb Electric116157-00). The top section of the hose 18 should be of sufficientlength to provide enough slack such that the hose 18 remains attached tothe patient transfer device 16 when the patient transfer device 16 istransferred from the top surface of the patient trolley 14 to thepatient surface of the target modality (e.g., an MRI table). The topsection of the hose 18 may also be disconnected when not in use.

Two telescoping pillars 22 a, 22 b are connected to the underside of thetop portion and the base portion 15 of the patient trolley 14. Thepillars 22 a, 22 b are telescoping, so that the elevation of the topsurface, and consequently the patient transfer device 16, may beadjusted relative to the base portion 15. For example, according to oneexemplary embodiment of the invention, pillars 22 a, 22 b may include atelescopic pillar such as the TELEMAG TLG system of SKF Group (e.g.,model no. TLG 10/11-A, TLG 10/11-B, and TLG 10/11-C or other similarmodels such as SKF TLG10-CA34F-000). As understood by those of skill inthe art, the patient trolleys according various embodiments of theinvention may include only one pillar or, alternatively, two or morepillars.

To ensure safe transfer of a patient from the patient trolley to thetarget modality, the elevation of the top surface of the patient trolleyshould be about equal to the elevation of the patient surface of thetarget modality. The base portion 15 may include a plurality of castorsor wheels 34 a, 34 b, so that the trolley system is positionableadjacent the MRI apparatus within the MRI environment. The wheels 34 a,34 b are preferably in the form of casters for optimal maneuverability.For example, the wheels 34 a, 34 b according to one exemplary embodimentinclude castors provided by Darcor Limited of Toronto, Canada (e.g.,model no. T-CLM6-PD). The base portion 15 may include an optional cover13 that acts as a housing within which various components of the patienttrolley 14 are mounted.

Referring to FIG. 4, a schematic representation of the base portion 15of another embodiment of the present invention is provided. In theembodiment of FIG. 4, the cover 13 has been excluded from the baseportion 15 revealing the components within the uncovered base portion30. Mounted to the base 32 of the uncovered base portion 30 are twoactuators 22 a, 22 b, actuator motors 24 a, 24 b, blower 19 (and/orvacuum pump), battery pack 26, and control unit 28. The plurality ofwheels 34 a, 34 b may also be attached to the underside of the baseportion 15. The battery pack 26 is connected to the actuator motors 24a, 24 b, blower 19, and control unit 28, thereby providing sufficientpower to operate the system. Types of batteries include, but are notlimited to, lithium ion, lead acid, and nickel cadmium, the preferredembodiment being lithium ion.

As explained above, it is preferred that the motors, blower, controlunit, and/or battery pack are mounted to the base portion to minimizethe effect of the magnetic field of the MRI on the operation of themotors during use of the actuator or the blower during a patienttransfer. In one embodiment, the blower may be mounted on the undersideof the trolley top as the blower is normally not required to operatewhile the actuators are moving, which would cause the running motor tobe moving through the magnetic field of the MRI, creating additionalinduced current. The blower can optionally be positioned in a weakerportion of the magnetic field. For example, mounting the blower closerto the distal end of the patient trolley relative to the MRI machineminimizes the potential for interference by the magnetic forces on theblower. More preferably, the components in the base of the patienttrolley are mounted, such that the elevation of one or more of thesecomponents is fixed relative to the floor upon which the patient trolleytravels. Alternatively, the elevational travel of the components can bepermitted and limited. For systems in which it is desirable to have thetrolley configuration be symmetric from one operator end to the other,it is possible to mount the electronic components near the centerline ofthe trolley between each end. This minimizes the strength of themagnetic field to which the electronics are subjected when moved intothe MRI machine in either orientation.

According to various embodiments of the present invention, it ispreferred to include a blower that is firmly attached to the trolley,i.e. not separately portable. A separately portable blower is likely tocontain ferromagnetic material and when not firmly attached to thetrolley can pose a severe risk of becoming a projectile in an MRIenvironment.

It is possible for the magnetic forces generated by the MRI machine toovercome the force of gravity or the force holding such a blower inposition because the mass of the blower is not sufficient to resist theattraction force generated by the MRI machine. If the blower is notmaintained at a safe distance from the MRI machine, the blower may beattracted by and pulled into the bore of the MRI machine. This is apotentially dangerous occurrence because the blower may strike andinjure an operator or patient that is also in the vicinity of the MRImachine. It may also damage the MRI machine or the blower itself.Previously, blowers have been placed outside the room in which the MRIis located to mitigate this risk.

Therefore, it is preferable that various embodiments of the patienttrolley according to the present invention include a blower that isfixed on the patient trolley, preferably at a position that will remainat a distance from the MRI machine at which the MRI will not interferewith the functioning of the blower motor. Furthermore, it has beendiscovered that the configuration of the blower's location on thepatient trolley according to the various embodiments of the presentinvention reduces the magnetic attraction force created by theferromagnetic components of the blower.

Similarly, if the blower for the patient transfer device and the motoror motors used to operate the actuator of the patient trolley includeelectric motors, the strength of the MRI machine also has the potentialto disrupt the operation of the motors. As understood by those of skillin the art, electric motors typically utilize magnetic fields to producemechanical motion, providing a driving mechanism. These motors cancontain both electromagnets and fixed magnets. These electric motors maybe disrupted by an external magnetic field. Therefore, the configurationof the motor and blower in the base of the patient trolleys according tovarious embodiments of the present invention are necessary to ensureproper functioning of the lifting mechanism and delivering air to thepatient transfer device.

As explained above, the blower is preferably mounted in the base of thepatient trolley sufficiently far away from the bore of the MRI machine,such that the magnetic field of the MRI does not interfere with theoperation of the blower. With respect to the pillar motors, some liftingmechanisms include multiple stages with a motor incorporated in eachelevating lift of the stage. In such a configuration, the operation ofthe electric motor may be disrupted by the magnetic field of the MRImachine, if the motor is elevated to a position within a strong fieldor, forced to operate while moving through a strong magnetic field. Forvarious embodiments of the present invention, it is preferred to use anactuator that is configured, such that the motor remains at or withinthe base portion of the patient trolley. This may be achieved by usingan embodiment of the pillars as illustrated in FIG. 5.

In FIG. 5, pillar 22 a is illustrated in an extended position. Thepillar 22 a is preferably limited to two sections, a bottom section 40that is mounted to the base of the patient trolley, and a top section42, which is telescoping and moves relative to the bottom section 40.The motor for the pillar 22 a may be mounted within the bottom section40 of the pillar 22 a, such that the elevation of the motor does notchange as the top section 42 is raised. As understood by one of skill inthe art, the materials used to fabricate the pillar should be selectedto accommodate the weight of the top portion of the patient trolley inaddition to the weight of a patient transfer device and a patient. Thepillar motors should also be selected, such that the motors are able togenerate sufficient power to safely raise and lower the patient. If apillar containing more than two sections is used, it is preferable toemploy a mechanism that allows the motor or motors to remain stationarywhile driving the moving sections.

According to another embodiment of the present invention, a method oftransferring a patient to a target modality within an MRI environment isprovided. The method comprises first positioning a trolley systemadjacent the target modality within the MRI environment. The trolleysystem comprises a patient trolley having a patient support surface anda base portion. Positioning includes ensuring that the patient supportsurface is about parallel and adjacent to the patient support surface ofthe target modality. Next, a user may optionally raise the patientsupport portion relative to the base portion by actuating a lift tochange the elevation of the patient support portion relative to the baseportion. This may be optional because in certain circumstances theheight of the patient support portion may be approximately equal to theheight of the target modality, therefore adjustment is not necessary insuch circumstances. In fact, a fixed height trolley (without motor andactuator) may be provided according to aspects of this invention.Alternatively, the height of the target modality may be adjusted to beapproximately equal to the height of the patient support portion. If thetrolley system also includes a patient transfer device on the patientsupport surface, the method further comprises providing air to the airbearing of the patient transfer device and transferring the patienttransfer device from the patient support portion to the target modality.

EXAMPLES

Advantageous properties of aspects of this invention can be observed byreference to the following examples, which illustrate but do not limitthe invention.

MR Compatibility Test Procedure

The following MR Compatibility Test Procedure is used to determine MRCompatibility according to aspects of this invention. It is used todetermine the magnetic attraction force of a trolley system as well asthe operability of one or more electric motors included in the trolleysystem. Reference is made to FIG. 6, which illustrates schematically therelative position of a trolley system and an MRI device.

I. Test Setup

Place the trolley system on a hard flat surface (such as a linoleumfloor), ensuring that brakes of the trolley system are in their unlockedposition.

II. Procedure

A. Testing Equipment

-   -   The MRI device used is a Siemens MAGNETOM Verio 3T MRI scanner        device or equivalent nominal 3T MRI scanner with a horizontal B₀        orientation. Other equivalent nominal 3T MR scanners are        available from Siemens, GE, Philips, Toshiba and others.

B. Trolley Orientation—Gantry End Against Bore

-   -   Lower the trolley system to its lowest position. Orient the        trolley such that the gantry end is facing the bore of the        magnet and the trolley is parallel to the MRI table. Slowly        introduce the trolley into the magnetic field until the gantry        end is against the face of the bore, or the gantry end is as        close as possible to the magnet.

C. Force Measurement

-   -   Using a force gauge, ensure there is no load on the gauge and        verify the dial is zeroed. To zero the gauge, rotate the dial        face so that the gauge needle rests above the zero mark.    -   At the locations described in FIG. 6, use the force gauge to        pull the trolley horizontally away from the bore of the magnet        until the trolley begins to move and record the Lateral Force        Measurement and the Longitudinal Force Measurement.    -   Repeat these measurements with the trolley in its highest pillar        position.

D. Electronic Functionality Test

-   -   While the trolley is against the face of the bore in the        position shown in FIG. 6, verify that each of the following        electronic systems function, if present in the tested trolley.        -   1. Pillar Travel            -   For a trolley system having height adjustment with one                or more electric motors, test the operation of those                motors. For example, using ‘up’ and ‘down’ arrows on a                control panel of one embodiment of the trolley system,                move the pillars from their lowest position to their                highest position. For embodiments with plural pillars,                the pillars should reach their full extent of travel                synchronized with each other.        -   2. Blower Activation            -   For a trolley system having one or more blowers with                electric motors, test the operation of those motors. Put                the brakes in their locked position. Actuate the                blower(s). Actuating any of the blowers should cause the                blower to turn on and air to travel down the hose.        -   3. Vacuum Activation            -   For a trolley system having one or more vacuum pumps                with electric motors, test the operation of those                motors. Put the brakes in their locked position. Actuate                the vacuum pump(s). Actuating any of the vacuum pumps                should cause the actuated vacuum pump to turn on and                produce vacuum.

E. Trolley Orientation—Operator End Against Bore

-   -   Lower the trolley to its lowest position. Orient the trolley        such that the operator end is facing the bore of the magnet and        the trolley is parallel to the MRI table. Slowly introduce the        trolley into the magnetic field until the operator end is        against the face of the bore, or the operator end is a close as        possible to the magnet.    -   Repeat the Force Measurement and Electronic Functionality Test        above.

Example 1

In order to determine the magnetic attraction force of a trolley systemmade according to an embodiment of the present invention, a trolleysimilar to the embodiment illustrated in FIG. 3 was tested proximate toa Siemens MAGNETOM Verio 3T MRI device. A Siemens MAGNETOM Espree 1.5TMRI device was also used for comparison purposes. The trolley includedstowable rails 21, lifts 22 a, 22 b, as well as a memory system in orderto store multiple pre-selected positions for the lifts 22 a, 22 b. Theoperator end of the trolley is the right-side end of the trolley in theview provided in FIG. 3, where the hose 18 is located, and the gantryend is the left-side end. The trolley 14 was introduced into themagnetic field until the gantry end was against the face of the bore. Atthe locations illustrated in FIG. 6, the brakes on the trolley weredisengaged and a force gauge was used to pull the trolley 14 away fromthe bore of the magnet until the trolley 14 began to move and themaximum force was recorded. This procedure was repeated after extendingthe lifts 22 a, 22 b to raise the trolley 14 to its highest elevationand deploying the side rails 21 to the raised position. The procedurewas repeated again with the trolley 14 in the raised and loweredpositions after turning the trolley 14 180 degrees, such that theoperator end of the trolley 14 was against the bore of the MRI.

The results of the force measurement testing are provided in thefollowing table:

Force MRI Trolley Pull Measurement (T) Configuration Direction (lbsforce) Gantry End 1.5 Lowered Lateral 7 Against Bore 1.5 LoweredLongitudinal 6 1.5 Raised Lateral 5 1.5 Raised Longitudinal 10 3 LoweredLateral 10 3 Lowered Longitudinal 10 3 Raised Lateral 9.5 3 RaisedLongitudinal 12 Operator End 1.5 Lowered Lateral 5.5 Against Bore 1.5Lowered Longitudinal 5 1.5 Raised Lateral 7 1.5 Raised Longitudinal 7 3Lowered Lateral 8 3 Lowered Longitudinal 11 3 Raised Lateral 10 3 RaisedLongitudinal 11

In each of the four orientations described above, the function of theelectronic systems was tested in proximity of the 1.5T and 3T MRI. Theelectromechanical functions of the following user-interfacing componentswere tested: the blower, the vertical operation of the pillar, thememory control of the pillar height, a pillar calibration module, thecontrol panel, an alarm, a main power switch, and a safety interlock. Ina first test, the pillars 22 a, 22 b were lowered and raised from theirlowest to highest positions. In a second test, four separate memorypositions for the pillars 22 a, 22 b were selected to determine if thetrolley was able to correctly alternate between the various heightsettings. In a third test, an automatic calibration mode of the pillars22 a, 22 b was performed. In a fourth test, the blower was operatedwhile the brakes on the trolley wheels were engaged to test thefunctioning of a safety interlock. In a fifth test, the blower wasoperated while the brakes were disengaged to test the functioning of analarm. In a sixth test, a control panel stop function was tested todetermine whether the control panel and blower buttons would remainunresponsive. In a seventh test, the main power switch was toggled todetermine whether the electronic system was able to start up normally.All of the electronic functions of the trolley 14 operated correctly andexhibited no interference while in proximity of either MRI magnet.

According to one aspect of the invention, a trolley system is configuredto transport a patient within an MRI room, the trolley systemcomprising: a patient support portion configured to support the patient;a base portion configured for movement relative to a floor; at least oneactuator coupled to the patient support portion and the base portion,the at least one actuator being configured to move the patient supportportion relative to the base portion and to change the elevation of thepatient support portion relative to the base portion; and at least oneelectric motor coupled to the at least one actuator, wherein the atleast one electric motor is mounted such that the elevation of the atleast one electric motor is fixed relative to the base portion; whereinthe trolley system is MR Compatible with a maximum magnetic attractionforce less than or equal to 50 lbs force.

According to another aspect of the invention, a trolley system isconfigured to transport a patient within an MRI room, the trolley systemcomprising: a patient support portion configured to support the patient;a base portion configured for movement relative to a floor; and anelectric blower coupled to the base portion of the trolley system andfixed to prevent movement of the electric blower relative to the trolleysystem, the electric blower being configured to deliver air to a featureof the trolley system; wherein the trolley system is MR Compatible witha maximum magnetic attraction force less than or equal to 50 lbs force.

According to another aspect of the invention, a method of delivering apatient to a bore of an MRI device is provided, the method comprising:positioning a trolley system proximate to the bore of the MRI device,such that an end of the trolley system is facing the bore of the MRIdevice, the trolley system being MR Compatible with a maximum magneticattraction force less than or equal to 50 lbs force and including apatient support portion configured to support the patient, a baseportion configured for movement relative to a floor, an actuator coupledto the patient support portion and the base portion, and one or moreelectric motors coupled to the actuator; optionally raising the patientsupport portion relative to the base portion by actuating the actuatorto change the elevation of the patient support portion relative to thebase portion; and conveying the patient onto a target modality.

According to another aspect of the invention, an imaging system isprovided comprising: an MRI device; and a trolley system according toaspects of this invention.

According to another aspect of the invention, a trolley system isconfigured to transport a patient within an MRI environment, the trolleysystem comprising: a patient support portion configured to support thepatient; a base portion configured for movement relative to a floor; atleast one actuator coupled to the patient support portion and the baseportion, the at least one actuator being configured to move the patientsupport portion relative to the base portion and to change the elevationof the patient support portion relative to the base portion; and atleast one electric motor coupled to the at least one actuator; whereinthe at least one electric motor is mounted such that the elevation ofthe at least one electric motor is fixed relative to the base portion;and wherein the trolley system is positionable adjacent an MRI apparatuswithin the MRI environment and the magnetic field of the MRI does notinterfere with the operation of the at least one electric motor.

According to another aspect of the invention, a trolley system isconfigured to transport a patient within an MRI environment, the trolleycomprising: a patient support portion configured to support the patient;an electric blower coupled to a feature of the trolley system and fixedto prevent movement of the electric blower relative to the trolleysystem, the electric blower being configured to deliver air to thepatient transfer device; wherein the trolley system is positionableadjacent an MRI apparatus within the MRI environment and the magneticfield of the MRI does not interfere with the operation of the electricblower.

According to another aspect of the invention, a method of transferring apatient to a target modality within an MRI environment is provided, themethod comprising: positioning a trolley system adjacent the targetmodality within the MRI environment, the trolley system including apatient support portion configured to support the patient, a patienttransfer device comprising an air bearing on the patient supportportion, a base portion configured for movement relative to a floor, anactuator coupled to the patient support portion and the base portion,and one or more electric motors coupled to the actuator, all of the oneor more electric motors being mounted such that the elevation of theelectric motors is fixed relative to base portion; optionally raisingthe patient support portion relative to the base portion by actuatingthe actuator to change the elevation of the patient support portionrelative to the base portion; delivering air to the air bearing; andtransferring the patient transfer device from the patient supportportion of the trolley to the target modality; wherein the magneticfield of the MRI does not interfere with the operation of all of the oneor more electric motors during actuation of the actuator.

According to another aspect of the invention, a method of delivering apatient to a bore of an MRI device is provided, the method comprisingpositioning a trolley system proximate to the bore of the MRI device,such that an end of the trolley system is facing the bore of the MRIdevice, the trolley system being MR Compatible with a maximum magneticattraction force less than or equal to 50 lbs force and including apatient support portion configured to support the patient, a patienttransfer device positioned on the patient support portion, a baseportion configured for movement relative to a floor, and an electricblower, actuating the electric blower to deliver air to the patienttransfer device, thereby supplying air to the patient transfer device tofacilitate movement of the patient; and conveying the patient onto atarget modality.

While preferred embodiments of the invention have been shown anddescribed herein, it will be understood that such embodiments areprovided by way of example only. Numerous variations, changes andsubstitutions will occur to those skilled in the art without departingfrom the spirit of the invention. Accordingly, it is intended that theappended claims cover all such variations as fall within the spirit andscope of the invention.

What is claimed:
 1. A trolley system configured to transport a patientwithin an MRI room, the trolley system comprising: a patient supportportion configured to support the patient; a base portion configured formovement relative to a floor; at least one actuator coupled to thepatient support portion and the base portion, the at least one actuatorbeing configured to move the patient support portion relative to thebase portion and to change the elevation of the patient support portionrelative to the base portion; and at least one electric motor coupled tothe at least one actuator, wherein the at least one electric motor ismounted such that the elevation of the at least one electric motor isfixed relative to the base portion and the elevation of the at least oneelectric motor does not change when the at least one actuator moves thepatient support portion relative to the base portion to change theelevation of the patient support portion relative to the base portion,the at least one electric motor being mounted to a lower portion of theat least one actuator such that the at least one electric motor remainswithin a weaker portion of a magnetic field generated by an MRIapparatus in the MRI room, thereby reducing the effect of the magneticfield on the operation of the at least one electric motor during use ofthe at least one actuator; wherein the trolley system is MR Compatiblewith a maximum magnetic attraction force less than or equal to 50 lbsforce; wherein the trolley system is positionable adjacent the MRIapparatus within the MRI room; and wherein the magnetic field generatedby the MRI apparatus does not interfere with operation of the at leastone electric motor when the trolley system is positioned adjacent theMRI apparatus, such that the at least one electric motor operates the atleast one actuator to change the elevation of the patient supportportion relative to the base portion while adjacent the MRI apparatusand while the magnetic field is generated by the MRI apparatus.
 2. Thetrolley system of claim 1, wherein the electric motor is mounted to alower portion of the actuator in such a way that the displacement of theelectric motor with respect to the base portion is prevented or limited.3. The trolley system of claim 1, further comprising a patient transferdevice having an air bearing, and an electric blower coupled to thepatient transfer device and configured to deliver air to the airbearing, the air bearing being configured to facilitate movement of thepatient transfer device relative to the patient support portion of thetrolley system.
 4. The trolley system of claim 1, wherein the at leastone actuator includes at least one telescoping stage.
 5. The trolleysystem of claim 1, wherein the trolley system is MR Compatible with amaximum magnetic attraction force less than or equal to 25 lbs force. 6.The trolley system of claim 1, wherein the at least one actuatorincludes a scissor lift mechanism.
 7. The trolley system of claim 3,wherein the feature of the trolley system to which air is delivered fromthe electric blower is at least one of a patient transfer device, apatient bed, a wound care bed, a bed that provides alternatingpressures, a surface designed for therapeutic applications, a surfacedesigned for patient comfort, a skin protection surface, an air powereddevice, and a compression surface.
 8. A method of delivering a patientto a bore of an MRI apparatus using the trolley system of claim 1, themethod comprising: positioning the trolley system proximate to the boreof the MRI apparatus, such that an end of the trolley system is facingthe bore of the MRI apparatus, optionally raising the patient supportportion of the trolley system relative to the base portion of thetrolley system by actuating the at least one actuator to change theelevation of the patient support portion relative to the base portion;and conveying the patient onto a target modality.
 9. An imaging systemcomprising: an MRI apparatus; and a trolley system according to claim 1.10. The method of claim 8, further comprising: delivering air to the airbearing; and transferring the patient transfer device from the patientsupport portion of the trolley system to the target modality; whereinthe magnetic field generated by the MRI does not interfere with theoperation of all of the one or more electric motors during actuation ofthe actuator.